Granted Patent
Utility
US 6,091,866 · App. 09/144,447
Optical isolator
Inventor:
Yihao Cheng
Patented Case
View Patent ↗
Granted: Jul 18, 2000
Filed: Sep 1, 1998
Inventor
Yihao Cheng
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.